Under German law there are several constraints to a trademark. These are mainly limitation, forfeiture, descriptive use, exhaustion, non-use.

Limitation. Limitation for claims based on infringement is 3 years from the date the trademark proprietor is aware of the infringement. Regardless of the proprietor’s awareness, such claims are limited to a max of 30 years from the date of infringement.

Forfeiture. A trademark proprietor tolerating an infringement for 5 consecutive years will lose the right to claim based on this infringement if the infringer does not act in bad faith.

Descriptive use. Descriptive use of protected signs (e.g. to indicate the purpose of a product or service) may not be prohibited.

Exhaustion. Distribution of trademarked goods within the European Economic Area (EEA) may not be prohibited if these goods have been put on the market in the EEA before with the consent of the trademark proprietor (“Grey Import”).

Non-use. No infringement claims may be asserted against third parties if the trademark has not been put to genuine use within a period of five consecutive years prior to asserting the claim.